ios - iPad 上的 gdb 无法转储内存

Question

我正在尝试查看在我的 iPad 上运行的应用程序的内存。我有应用程序的 pid，我可以使用 gdb 附加到进程。

iPad:~/dev root# gdb -p 3839
GNU gdb 6.3.50.20050815-cvs (Fri May 20 08:08:42 UTC 2011)
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "--host=arm-apple-darwin9 --target=".
/private/var/root/dev/3839: No such file or directory
Attaching to process 3839.
0x35824004 in ?? ()
(gdb) 

但是，当我尝试转储其中一个内存区域时:

(gdb) info mach-regions
Region from 0x22000 to 0x24000 (---, max r-x; copy, private, not-reserved)
   ... from 0x24000 to 0x269000 (---, max r-x; copy, private, not-reserved)
[...]
   ... from 0x267a000 to 0x267b000 (---, max rwx; copy, private, not-reserved)
   ... from 0x267b000 to 0x267c000 (---, max rwx; copy, private, not-reserved)
   ... from 0x267c000 to 0x267d000 (---, max rwx; copy, private, not-reserved)
   ... from 0x267d000 to 0x267f000 (---, max rwx; copy, private, not-reserved)
   ... from 0x267f000 to 0x2680000 (---, max rwx; copy, private, not-reserved)
[...]
(gdb) dump binary memory output.bin 0x267c000 0x267d000

我收到这个错误:

gdb stack crawl at point of internal error:
0   gdb                                 0x00170e74 internal_vproblem + 124
1   gdb                                 0x0016dd68 internal_verror + 52
2   gdb                                 0x0016dd94 align_down + 0
3   gdb                                 0x0016def8 gdb_check_fatal + 36
4   gdb                                 0x001eba9c mach_xfer_memory + 588
5   gdb                                 0x000c7ca8 default_xfer_partial + 256
6   gdb                                 0x000ca04c target_xfer_partial + 1004
7   gdb                                 0x000ca404 target_read_partial + 56
8   gdb                                 0x000ca488 target_read + 120
9   gdb                                 0x000ca674 target_read_memory + 68
10  gdb                                 0x00003f5c dump_memory_to_file + 276
11  gdb                                 0x0016c804 execute_command + 1160
12  gdb                                 0x000aba88 command_handler + 228
13  gdb                                 0x000acd94 command_line_handler + 768
14  gdb                                 0x002236b4 rl_callback_read_char + 160
../../gdb-1518/src/gdb/macosx/macosx-nat-mutils.c:772: internal-error: assertion failure in function "mach_xfer_memory": r_end >= cur_memaddr

A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n) y

一旦我退出 gdb，应用程序也会崩溃。

看起来我做的一切都是对的，在这里...为什么会发生错误？如何让它发挥作用？

我在第一代 iPad 上运行 iOS 5.1.1。

Answer 1

啊，显然是 Cydia 附带的 GDB 版本 doesn't work on iOS 5 .这些说明对我有用:

GNU Debugger (gdb) is used to analyze the run time behavior of an iOS application. In recent iOS versions, GNU Debugger directly downloaded from the Cydia is broken and not functioning properly. Following the Pod 2g blog post also did not help me.

To get rid of this problem, add http://cydia.radare.org to cydia source and download the latest GNU Debugger (build 1708). GDB build 1708 is working for iOS 5.x.